The embodiments disclosed herein related to an apparatus, a system and/or a method for filtering and/or separating particles. More specifically, embodiments disclosed herein relate to modular filter screens and methods using modular filter screens.
Filter screens are used to filter particles in industrial filtration systems. For example, shale shakers use filter screens to separate drill cuttings from drilling fluid in on-shore and off-shore oilfield drilling. The filters screens have a wire mesh stretched across a frame. The frame is a rectangular grid of support ribs that divide the frame into an orthogonal array of cells. The mesh is secured to the ribs as well as to the surrounding frame. Additionally, the cells in the frame have the same orientation.
The wire mesh has different mesh sizes defined by the size of the apertures between the individual wires in the mesh. The size of the apertures of the mesh is selected depending on the size of the particle to be filtered. Particles smaller than the aperture pass through the wire mesh and through the cells between the ribs. The remaining particles are discharged on an end of the filter screen.
Over the life of the filter screen, particle movement through the wire mesh, as described here, may cause wear on the wire mesh. Eventually, holes form in the wire mesh that allow larger particles to pass through the screen. Certain regions of the mesh are more prone to damage than other regions. For example, the mesh stretched across cells below where the particles are introduced experience greater wear than the mesh stretched across cells towards the exit end of the screen.
Conventional filter screens may be heavy and cumbersome to transport. Additionally, the filter screens are bulky. Locations with limited space, such as drilling rigs, may not be able to store extra filter screens. Therefore, replacement filter screens are not always available.
To extend the operational life of the screen, plugs are used to block particles from going through damaged wire mesh. These plugs fit into the cells and have a solid surface oriented towards the damaged mesh. The plugs fit into the cell from below and are hammered into place. As such, the plugs are designed to block particles from traveling through the damaged screen and the cell. Therefore, the cells with the plugs no longer filter particles.
As more of the plugs are installed into more of the cells, the filtering ability of the filter screen is reduced. Eventually, the filter screen must be replaced. Moreover, the plugs cannot be reused as they are hammered in place without a way to remove them. When the filter screen is discarded, the installed plugs are also discarded.
Further, incorporating a design into the filter screen that allows plugs to snap into the cells increases development time and cost. Additionally, retrofitting a system so that plugs may be used to patch a hole in the mesh requires time and significant retooling.